Analog Devices AD1385TD-883B, AD1385TD, AD1385KD Datasheet

a 16-Bit 500 kHz

Wide Temperature Range Sampling ADC

AD1385

FEATURES 16-Bit Resolution

500 kHz Sampling Rate

Differential Linearity Autocalibration Specified over –558C to +1258C Range

SNR 90 dB @ 100 kHz (min)

THD –88 dB @ 100 kHz (min) 0.0006% FSR DNL (typ) 0.0015% FSR INL (typ)

No Missing Codes

65, 610 V Bipolar Input Ranges

Zero Offset Autocalibration

APPLICATIONS

Medical Imaging

CAT

Magnetic Resonance

Radar

Vibration Analysis

Parametric Measurement Unit (ATE)

Digital Storage Oscilloscopes

Waveform Recorders

Analytical Instruments

PRODUCT DESCRIPTION

The AD1385 is a complete 500 kHz, 16-bit, sampling analog- to-digital converter contained in a single package. Its differential linearity autocalibration feature allows this high resolution, high speed converter to offer outstanding noise and distortion performance, as well as excellent INL and DNL specifications, over the full military temperature range. Autocalibration effectively eliminates DNL drift over temperature.

The AD1385 architecture includes a low noise, low distortion track/hold, a three pass digitally corrected subranging ADC, and linearity calibration circuitry. A complete linearity calibration requires only 15 ms. Precision thin-film resistors and a proprietary DAC contribute to the part’s outstanding dynamic and static performance.

FUNCTIONAL BLOCK DIAGRAM

The AD1385 uses four power supplies, ±5 V and ±15 V, and an external 10 MHz clock. Power dissipation is nominally 2.76 W. Two user selectable bipolar input ranges, ±5 V and ±10 V, are provided. Careful attention to grounding and a single package make it easy to design PCBs to achieve specified performance.

The AD1385’s pinout is nearly identical to that of the AD1382, a factory calibrated 16-bit, 500 kHz SADC. Just two additional connections, to enable and monitor autocalibration, are required. This commonality provides an easy upgrade path to extend system performance and operating temperature range.

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Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: [phone] Fax: [phone]

	(TA = +258C, VS = 615 V, VDD = +5 V, VSS = –5 V, 10 MHz External Clock,
AD1385–SPECIFICATIONS unless otherwise noted)
		AD1385KD			AD1385TD
Parameter	Min	Typ	Max	Min	Typ	Max		Units
RESOLUTION	16			16				Bits
ANALOG INPUT		±5, ±10			±5, ±10
Input Ranges								V
Input Impedance	2.45	2.5	2.55	2.45	2.5	2.55		kΩ
TRANSFER CHARACTERISTICS
(Combined ADC/Track/Hold)		±0.0015			±0.0015
Integral Nonlinearity1, 2, TMIN to TMAX			±0.0015			±0.0015		% FSR3
Differential Nonlinearity1		±0.0006			±0.0006			% FSR
Drift, TMIN to TMAX		0.3			0.3			ppm/°C
Missing Codes, TMIN to TMAX		±0.05	None		±0.05	None
Gain Error4			±0.15			±0.15		% FSR
Drift, TMIN to TMAX		8	15		8	15		ppm/°C
Bipolar Zero4		±0.05	±0.10		±0.05	±0.10		% FSR
Drift, TMIN to TMAX		5	15		5	15		ppm/°C
PSRR		±0.006	±0.10		±0.006	±0.10		% FSR/V
Noise		70			70			μV rms
DYNAMIC CHARACTERISTICS2
±5 V FSR, VIN = –0.4 dB, TMIN to TMAX
Sample Rate			500			500		kHz
Signal-to-Noise Ratio5
f = 5 kHz	90	93		90	93			dB
f = 100 kHz	90	92		90	92			dB
f = 200 kHz	88	91		88	91			dB
Peak Distortion
f = 5 kHz	–90	–107		–90	–107			dB
f = 100 kHz	–88	–95		–88	–95			dB
f = 200 kHz	–82	–88		–82	–88			dB
Total Harmonic Distortion6
f = 5 kHz	–90	–105		–90	–105			dB
f = 100 kHz	–88	–95		–88	–95			dB
f = 200 kHz	–82	–88		–82	–88			dB
DYNAMIC CHARACTERISTICS2
±10 V FSR, VIN = –0.4 dB, TMIN to TMAX
Sample Rate			500			500		kHz
Signal-to-Noise Ratio5
f = 5 kHz	90	95		90	95			dB
f = 100 kHz	90	94		90	94			dB
f = 200 kHz	88	93		88	93			dB
Peak Distortion
f = 5 kHz	–90	–108		–90	–108			dB
f = 100 kHz	–80	–87		–80	–87			dB
f = 200 kHz	–74	–82		–74	–82			dB
Total Harmonic Distortion6
f = 5 kHz	–90	–105		–90	–105			dB
f = 100 kHz	–80	–87		–80	–87			dB
f = 200 kHz	–74	–82		–74	–82			dB
DIGITAL INPUTS
Input Voltage
VIL			0.8			0.8		V
VIH	2.25		±200	2.25		±200		V
Input Current								μA
Input Capacitance		2			2			pF
Clock
Frequency		2.5–10			2.5–10			MHz
Duty Cycle		40-60			40-60			%
Aperture Delay7		7			7			ns
DIGITAL OUTPUTS
Output Voltage
VOL @ IOL = 3.2 mA		0.2	0.4		0.2	0.4		V
VOH @ IOH = –3.2 mA	2.4	4.5		2.4	4.5			V
Output Capacitance		4	±200		4	±200		pF
Leakage, Outputs Disabled								μA

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							AD1385
		AD1385KD			AD1385TD
Parameter	Min	Typ	Max	Min	Typ	Max	Units
OUTPUT CODING	Complementary Offset Binary or Complementary Twos Complement
INTERNAL REFERENCE
Voltage	9.990		10.010	9.990		10.010	V
Current	2	5		2	5		mA
Drift		5	15		5	15	ppm/°C
TEMPERATURE RANGE, CASE							°C
Specified	0		+70	–55		+125
Storage	–65		+150	–65		+150	°C
POWER REQUIREMENTS
Specified Operating Range
±VS	14.25		15.75	14.25		15.75	V
+VDD	4.75		5.25	4.75		5.25	V
–VSS	–5.25		–4.75	–5.25		–4.75	V
Current Drains
+VS		52	80		52	80	mA
–VS		48	75		48	75	mA
+VDD		104	160		104	160	mA
–VSS		148	200		148	200	mA
Power Dissipation		2.76	4.125		2.76	4.125	Watts

NOTES

1Integral linearity is inferred from FFTs. Differential linearity is derived from histograms.

2Performance over temperature is specified at the temperature at which the last calibration was performed. 3FSR = Full-Scale Range.

4Adjustable to zero.

5SNR excludes harmonics 2-9 of the fundamental. 6THD includes harmonics 2-9 of the fundamental.

7Aperture delay is the time from the rising edge on the Hold Command Input to the opening of the switch in the Track/Hold.

Specifications subject to change without notice.

TIMING SPECIFICATIONS1, 2	(TA = –558C to +1258C, VS = 615 V, VDD = +5 V, VSS = –5 V)
Parameter	Design Minimum	Typ	Unit	Description
START COMMAND
tSCS	10		ns	Setup Time
tSCH	10		ns	Hold Time
AUTOZERO
tAZS	10		ns	Setup Time
tAZH	20		ns	Hold Time
DATA VALID			CP3
tDVS		1.5		Setup Time
tDVH		0.5	CP3	Hold Time
HOLD COMMAND			CP3
tH		13		Hold Time
tD		7	ns	Delay Time
DATA STROBE			CP3
tDS		2		Pulse Width
tDSD		16.5	CP3	Delay
CALIBRATE PULSE WIDTH	20		ns
CALIBRATION STATUS		15	ms	Duration

NOTES

1Refer to Figures 17, 18 and 24.

2Design minimums are derived from worst case design analysis and/or simulation results. Typical values are based on characterization data. These specifications are not guaranteed or tested.

3The time duration for this parameter varies in direct proportion to the width of the Clock Pulse (CP).

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AD1385

ABSOLUTE MAXIMUM RATINGS*

+VS to AGND . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . . 18 V
–VS to AGND . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . –18 V
VDD to PGND . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . . . 7 V
VSS to PGND . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . . –7 V
AGND to PGND . . . . . . . . . . . . . .	. . . . . . . . . . . . . . ±0.3 V
Analog Inputs . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . . .±VS
Reference Input . . . . . . . . . . . . . . . .	. . . . . . . . . .0 V to +11 V
Digital Inputs . . . . . . . . . . . . . . . . . .	. . –0.3 V to VDD + 0.3 V
Output Short Circuit Duration
Reference Output . . . . . . . . . . . . .	. . . . . . . . . . . . Indefinite
Track/Hold Output . . . . . . . . . . .	. . . . . . . . . . . . . . . . 1 sec
Digital Outputs . . . . . . . . . . . . . .	1 sec for Any One Output
Case Temperature (Operating) . . . .	. . . . . . –55°C to +125°C
Storage Temperature . . . . . . . . . . . .	. . . . . . –65°C to +150°C

*Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

ORDERING GUIDE

	Temperature
Model	Range (Case)	Package Option*
AD1385KD	0°C to +70°C	DH-48A
AD1385TD	–55°C to +125°C	DH-48A
AD1385TD/883B	–55°C to +125°C	DH-48A

*DH-48A = Bottom Brazed Ceramic DIP.

AD1385 PIN CONNECTIONS

The AD1385 is housed in a 48-pin bottom-brazed ceramic bathtub package. The pinout is as follows:

Pin		Function		Pin	Function
1	CLOCK IN			48	VDD2 (+5 V POWER)
2	POWER GROUND			47	POWER GROUND
3	B1/B9 (MSB)			46	VSS2 (–5 V POWER)
4	B2/B10			45	AUTOZERO
5	B3/B11			44	B1 SELECT
6	B4/B12			43	POWER GROUND
7	B5/B13			42	POWER GROUND
8	B6/B14			41
					CAL
9	B7/B15			40	GAIN ADJUST
10		B8/B16 (LSB)		39	+10 V REFERENCE OUT
11		VDD1 (+5 V SIGNAL)		38	–VS1 (–15 V)
12		POWER GROUND		37	SIGNAL GROUND
13		VSS1 (–5 V SIGNAL)		36	+VS1 (+15 V)
14		SIGNAL GROUND		35	SIGNAL GROUND
15		DATA STROBE		34	DNC
16		HI/LO BYTE SELECT		33	DNC
17			DATA ENABLE	32	+10 V REFERENCE IN
		OE
18		START CONVERT		31	VIN B
19		HOLD COMMAND OUT		30	VIN A
20		SIGNAL GROUND		29	OFFSET ADJUST
21		+VS2 (+15 V)		28	CAL STATUS
22		HOLD COMMAND IN		27	TRACK/HOLD OUTPUT
23		–VS2 (–15 V)		26	SIGNAL GROUND
24		POWER GROUND		25	TRACK/HOLD INPUT

DNC = DO NOT CONNECT.

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD1385 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.

WARNING!

ESD SENSITIVE DEVICE

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AD1385

Figure 1. Spurious-Free Range vs. Input Amplitude,

±5 V Range, 2048-Point FFT, 500 kHz Sample Rate

Figure 2. Spurious-Free Range vs. Input Amplitude,

±10 V Range, 2048-Point FFT, 500 kHz Sample Rate

Figure 3. Full-Scale Sine Wave Power Spectral Density,

±5 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 4. Full-Scale Sine Wave Power Spectral Density,

±5 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 5. Full-Scale Sine Wave Power Spectral Density,

±5 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 6. 100 kHz Intermodulation Performance, ±5 V Range, 16384-Point FFT, 500 kHz Sample Rate

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AD1385

Figure 7. 200 kHz Intermodulation Performance, ±5 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 8. Full-Scale Sine Wave Power Spectral Density,

±10 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 9. Full-Scale Sine Wave Power Spectral Density,

±10 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 10. Full-Scale Sine Wave Power Spectral Density,

±10 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 11. 100 kHz Intermodulation Performance, ±10 V Range, 16384-Point FFT, 500 kHz Sample Rate

Figure 12. 200 kHz Intermodulation Performance, ±10 V Range, 16384-Point FFT, 500 kHz Sample Rate

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